Apparatus for automatically charging fluid under pressure



Aug. 1, 1967 A. E. ROUX 3,333,610

APPARATUS FOR AUTOMATICALLY CHARGING FLUID UNDER PRESSURE Filed Feb. 9,1965 2 Sheets-Sheet 1 oeur 2:44 9

APPARATUS FOR AUTOMATICALLY CHARGING FLUID UNDER PRESSURE Filed Feb. 9.1965 A. E. ROUX Aug. 1, 1967 2 Sheets-Sheet 2 United States Patent3,333,610 APPARATUS FOR AUTOMATICALLY CHARGING FLUID UNDER PRESSURE IAndr E. Roux, Eaubonne, France, assignor to Societe dEtudes, Invention,Recherche Application et de Realisations dite S.E.I.R.A.R., Paris,France Filed Feb. 9, 1965, Ser. No. 431,354 Claims priority, applicationFrance, Feb. 28, 1964, 965,502 13 Claims. (Cl. 141-40) The presentinvention relates to an automatic apparatus which is intended forfilling hermetic circuits containing volatile fluids, notably coolingcircuits. Hermetic construction of such circuits, generally calledsystems, ensures complete safety from the viewpoint of fluid tightness,but it requires high precision in the feed control during the operationof charging with cooling fluid, which precision is rendered necessary bythe fact that it is almost impossible subsequently to adjust this feedcontrol by reason of the very hermeticity of the systems.

The present invention is not concerned exclusively with coolingcircuits, but includes all apparatus operating with the aid of volatilefluids which have at normal temperature a saturated vapour pressurewhich is higher than atmospheric pressure, such as, for example, fireextinguishers, atomisers for perfumes, insecticides, paints, etc., whichnecessitate a precise fluid charge, whether the fluid be employed as afunctional object or a propulsion agent or vehicle.

The present invention relates to:

An automatic charging device for fluids whose saturated vapour pressureat ambient temperature is higher than atmospheric pressure, consistingof a first controlledfeed receptacle supplied with liquid through a ductextending from a reservoir and comprising means for automaticallyclosing the said duct; a second controlled-feed receptacle whose upperlevel is situated below the lower level of the first controlled-feedreceptacle, the second controlled-receptacle being connected on the onehand to the said first controlled-feed receptacle by a lower duct forthe liquid phase and by an upper duct for the vapour phase of the fluid,and being connected on the other hand by any appropriate duct to adevice for the distribution of the fluid comprising means forhermetically coupling it to the unit to be charged, the secondcontrolled-feed receptacle comprising means for simultaneously producingthe decoupling of the distribution member and the closing of its supplyduct, so that in a first operation the first controlled-feed receptacleis emptied by gravity into the second controlled-feed receptacle, and ina second operation the first controlled-feed receptacle is filled andthe second controlled-feed receptacle is simultaneously emptied into theunit to be charged.

The invention is hereinafter described with reference to theaccompanying drawings, in which:

FIGURE 1 is a diagrammatic illustration of a hermetic cooling system.

FIGURE 2 is an example of an embodiment of the invention applicable inparticular to the hermetic system of FIGURE 1.

FIGURE 3 is an example of a construction of a spray gun adapted toefiect the connection of the system of FIGURE 1.

Referring to the drawings, there may be seen in FIG- URE 1 a hermeticcooling system, of which the compressor 21 is connected by a tube 22 toan automatic valve 23 designed to effect the substantially instantaneousconnection of the system to the station to be charged with coolingfluid, and the disconnectio of the system at the end of the charging.

3,333,610 Patented Aug. 1, 1967 The charging station proper, which isadvantageously constructed in the form of a cabinet, comprises a duct 7for the supply of cooling fluid coming from a constantpressure reservoir(not shown). This duct supplies a dehydrator 8. Two dehydrators areshown in the drawing, because it is essential to be able to change adehydrator without interrupting the operation of the charging station.The shut-off valves are provided upstream and downstream of thedehydrators. The dehydrated fluid then passes through a shut-off valve9, a cock 10 for the manual adjustment of the rate of flow and anautomatic valve 11 and enters a controlled-feed receptacle 1. Thiscontrolledfeed receptacle contains a float 5 adapted to interrupt thelight beam illuminating the photoelectric cell 12 which controls theclosing of the automatic valve 11.

Masking of the cell 12 produces in addition the extinction of the lamp25 illuminating the said cell.

The controlled-feed receptacle 1 is in communication, with regard to thevapour phase, with an identical controlled-feed receptacle 2 through theduct 4.

The controlled-feed receptacles 1 and 2 are also in communication, withregard to the liquid phase, through a duct 3 comprising a cock 13 forthe adjustment of the rate of flow and an automatic valve 14, closing ofwhich is controlled'by a photoelectric cell 15, of which the controllight beam may be masked by a float 6.

The same float 6 may, in the lower position in which it is illustrated,mask the light beam controlling another photoelectric cell 18, whichcell 18 controls in turn the opening of an automatic three-way valve 19supplying com pressed air to a jack 20 and provided with an exhaustoutlet 24.

The liquid contained in the controlled-feed receptacle 2 may flowthrough the flexible duct 16 to the mouthpiece 17, which is disposed ina spray gun provided with a trigger which can be operated to eifect theconnection to the mouthpiece 23 of the system to be charged.

The spray gun is diagrammatically illustrated in FIG- URE 3.

The fluid supply duct 16 leads to the mouthpiece 17. The duct 33supplies compressed air to the automatic three-way valve 19 disposed inthe grip. The jack 20 is disposed in the body of the gun. It consists ofa cylinder 41 in which there is slidably mounted the piston 36 urgedforwards by the spring 37. The piston 36 comprises an external fork 38fast with the ring 39 surrounding the mouthpiece 17.

The compressed air coming from the valve 19 can penetrate into thecylinder 41 situated in front of the piston 36.

The gun is provided with a trigger 34 which, by mechanical action,retracts the piston 36 and the ring 39 so as to permit engagement of themouthpiece 23, which is locked when the trigger 34 is released and whenthe ring 39 and the piston 36 move forwards. The detent or lever 35actuates a switch 35 which closes the circuit of the relays of thecharging station and permits preparation of the feed quantity necessaryfor the next charging.

The apparatus operates as follows: it will be assumed that one chargingoperation has just been etfected. The controlled-feed receptacle 1 isfull, and the float 5 has masked the photoelectric cell 12 which hasbrought about the closing of the valve 11 and the extinction of itsexcitation lamp 25. The excitation lamp 27 of the cell 15 isextinguished. The valve 14 is closed and the controlled-feed receptacle2 is empty. The float 6 has masked the cell 18 which has brought aboutthe extinction of its excitation lamp 26, the opening of the automaticvalve 19 and the excitation of a time delay relay 42. The piston 36 ofthe jack 20 is retracted under the action of the compressed air,bringing with it the fork 38 and the ring 39. The male mouthpiece 23 ofthe charged system is unlocked and is ejected from the mouthpiece 17 ofthe gun under the double action of the expansion of a spring disposed inthe mouthpiece 17 and traces of pressurised fluid remaining in thevolume contained in the very small space separating the two mouthpieces.The time delay relay closes the valve 19 and opens the exhaust outlet24, the compressed air contained in the space 41 being discharged intothe atmosphere and the piston 36 is moved under the action of the spring37 toward-the left as viewed in FIG. 3, and the ring 39 being returnedin the forward direction. The time delay relay produces in addition theignition of the excitation lamp 27 of the cell 15, which in turn causesthe opening of the automatic valve 14.

At this instant, the feed quantity is prepared by transfer of the fluidfrom the controlled-feed receptacle 1 to the controlled-feed receptacle2 merely under the action of gravity, at constant saturated vapourpressure, temperature and volume. This preparation of the feed quantitytakes place in the very short interval of time between the ejection ofthe spray gun at the end of one charging operation and the positioningof the same spray gun on a new apparatus to be charged.

When the float 6 masks the cell 15, it produces the closing of the valve14 and the extinction of the lamp 27. The station is ready to supply afurther charge.

The operator grasps the grip of the charging gun and actuates thetrigger 34 and subsequently the detent 35.

The trigger 34 retracts the piston 36 and the fork 38, which carrieswith it the ring 39. It is then possible to engage the mouthpiece 23 ofthe new system to be charged in the mouthpiece or chuck 17 of the gun,both mouthpieces comprising a normally closed valve which opens when thetwo mouthpieces are connected together.

On release of the trigger 34, the spring 37 expands and the ring 39 ismoved forwards, thus locking the mouthpiece 23. The fluid charge canthen flow into the system to be charged.

Actuation of the detent 35 brings about the excitation of relays whichignite the two lamps 25 and 26. The cells 12 and 18 are thus excited andthe cell 12 opens the valve 11.

There then simultaneously take place in the charging station a fillingof the controlled-feed receptacle and an emptying of the controlled-feedreceptacle 2. These two operations may be carried out at the same speedby adjustment of the cock 10. Since the two receptacles are incommunication by way of the duct 4, the two receptacles are at the samepressure and at the same temperature.

I At the end of the charging, the float masks the cell 12, thusproducing extinction of the lamp 25 and closing 'of the valve 11, andthe float 6 masks the cell 18, thus producing the extinction of the lamp26, the opening of the valve 19, the excitation of the time delay relay42 and the ejection of the spray gun.

All the operations take place at the same pressure which is thatsupplied by the fluid reservoir, in particular the preparation of thefeed quantity by flow from the controlled-feed receptacle 1 into thecontrolled-feed receptacle and the charging of fluid into the system tobe charged. I

The speed with which the controlled-feed receptacle 1 is filled may beadjusted by means of the cock 10. When this speed is the same as thespeed at which the fluid flows into the system to be charged, the volumeof liquid is constant in the charging station. The operation of thecharging station is then isothermal.

The described means afford great operating safety and prevent theoperating faults which result in over-charging and under-charging.

Under-charging is avoided since the fluid feed defined by the movementof the float 6 in the controlled-feed receptacle 2 is automaticallypoured into the apparatus to be charged.

Over-charging is avoided by automatic ejection of the spray gun at theend of the charging.

In the described apparatus, the charging is effected with a precisionhigher than 1% by volume. This precision could be increased by employingcontrolled-feed receptacles of greater height and smaller cross-section.

The vertical position of the photoelectric cells may be adjusted atwill. More particularly, the relative positions of the cells 15 and 18may be varied to adjust the feed quantity to be supplied to the systemto be charged.

With a feed quantity between 50 and 250 cc., the'charging of systems canbe carried out at an accelerated rate in the neighbourhood of 24-0operations per hour.

The capacity of the control-feed receptacles may vary within very widelimits, the lower limit being of the order of a cubic centimetre, andthe upper limit being that given to the controlled-feed receptacles, thecrosssectional areas of fluid flow being made proportional to thecapacities of the controlled-feed receptacles and to the desired speedsof flow which may be adjusted with the aid of the cocks 10 and 13.

In addition, the duct 4 affording communication between the twocontrolled-feed receptacles in regard to the vapour phase must have asufficient cross-section.

The charging station is advantageously constructed in the form of acabinet.

What I claim is:

1. Automatic charging apparatus for fluids whose saturated vapourpressure at ambient temperature is above atmospheric pressure,comprising a first controlled-feed receptacle fed with liquid through aduct extending from a reservoir and comprising means for automaticallyclosing the said duct, a second controlled-feed receptacle whose upperlevel is situated below the lower level of the first controlled-feedreceptacle, the second controlledfeed receptacle being on the one handconnected to the said first controlled-feed receptacle by a lower ductfor the liquid phase and by an upper duct for the vapour phase of thefluid, and on the other hand connected by any appropriate duct to afluid distribution member comprising means for hermetically coupling itto the unit to be charged, the second controlled-feed receptaclecomprising means for simultaneously producing the decoupling of thedistribution member and the closing of its supply channel, so that in afirst operation the first controlled-feed receptacle is emptied bygravity into the second controlled-feed receptacle and in a secondoperation the first controlled-feed receptacle is filled and the secondcontrolled-feed receptacle is simultaneously emptied into the unit to becharged.

2. Charging apparatus according to claim 1 made in the form of acabinet.

3. Charging apparatus according to claim 1, wherein the means forautomatically closing the ducts are automatic valves controlled byphotelectric cells whose excitation beam is masked by a float movingwithin the said controlled-feed receptacles.

4. Charging apparatus according to claim 3, wherein the means for theejection of the said mouthpiece con'rprises an automatic valve providedin a compressed-air duct and controlled by a photoelectric cell, ofwhich the excitation beam is masked by a float.

'5. Charging apparatus according to claim 1, wherein the means forfitting the mouthpiece of the said flexible duct to the unit to becharged comprises a spray gun including a device for locking themouthpiece of the unit to be charged.

6. Charging apparatus according to claim 5, wherein 5 the said spray guncomprises a jack having a piston fast with a ring by which the saidmouthpiece is locked.

9. Charging apparatus according to claim 5, wherein the said spray guncomprises a trigger and a detent adapted to be manually operated.

10. Charging apparatus according to claim 1, wherein dehydrators areprovided in the duct extending from the reservoir.

11. Charging apparatus according to claim 10, wherein a shut-0E valve isprovided in the said duct.

12. Charging apparatus according to claim 1, wherein cocks for theadjustment of the rate of flow are provided 5 justable along thecontrolled-feed receptacles.

References Cited UNITED STATES PATENTS 2,789,586 4/1957 McBean 141- 0LAVERNE D. GEIGER, Primary Exami H. S. BELL, Assistant Examiner.

1. AUTOMATIC CHARGING APPARATUS FOR FLUIDS WHOSE SATURATED VAPOURPRESSURE AT AMBIENT TEMPERATURE IS ABOVE ATMOSPHERIC PRESSURE,COMPRISING A FIRST CONTROLLED-FEED RECEPTACLE FED WITH LIQUID THROUGH ADUCT EXTENDING FROM A RESERVOIR AND COMPRISING MEANS FOR AUTOMATICALLYCLOSING THE SAID DUCT, A SECOND CONTROLLED-FEED RECEPTACLE WHOSE UPPERLEVEL IS SITUATED BELOW THE LOWER LEVEL OF THE FIRST CONTROLLED-FEEDRECEPTACLE, THE SECOND CONTROLLEDFEED RECEPTACLE BEING ON THE ONE HANDCONNECTED TO THE SAID FIRST CONTROLLED-FEED RECEPTACLE BY A LOWER DUCTFOR THE LIQUID PHASE AND BY AN UPPER DUCT FOR THE VAPOUR PHASE OF THEFLUID, AND ON THE OTHER HAND CONNECTED BY ANY APPROPRIATE DUCT TO AFLUID DISTRIBUTION MEMBER COMPRISING MEANS FOR HERMETICALLY COUPLING ITTO THE UNIT TO BE CHARGED, THE SECOND CONTROLLED-FEED RECEPTACLECOMPRISING MEANS FOR SIMULTANEOUSLY PRODUCING THE DECOUPLING OF THEDISTRIBUTION MEMBER AND THE CLOSING OF ITS SUPPLY CHANNEL, SO THAT IN AFIRST OPERATION THE FIRST CONTROLLED-FEED RECEPTACLE IS EMPTIED BYGRAVITY INTO THE SECOND CONTROLLED-FEED RECEPTACLE AND IN A SECONDOPERATION THE FIRST CONTROLLED-FEED RECEPTACLE IS FILLED AND THE SECONDCONTROLLED-FEED RECEPTACLE IS SIMULTANEOUSLY EMPTIED INTO THE UNIT TO BECHARGED.